Improvement in machines for drilling carriage-shackles



spindles a (t.

B'. CLARK, OF.PLAl\l'lSVILl`ll1l7 CONNECTICUT.

Letters Patent No. 107,875, d'aea october 4, 1810.

IMPRovl-:MENT ljN MAcHINEs Fon DRILLING CARRIAGYEQSHACKLES.

. The Schedule referred to in these Letters Patent and making part of the sama I, JAMES B. CLA'RIQof' Plantsville, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Machine for Drilling Carriage-shackles, of which the following is a specilication.

My invention consists in the employment of a revolving frame, provided with clamps, and arranged betwecn'two series ot' revolving drills andtaps, as

, hereafter described.

In the accompanying drawing- Figure lis a front elevation of my machine, and

Figure 2 is a sectional view of the same oli line A designates the base ofthe machine, which is provided with uprights B BBB, in which are the bearings for the three pairs of spindles, au.

In tig. 1 the rear pair ot' lower spindles Aare hid froniview by the pair .immediately in front ot' them, but the proper position of all is indicatedby the brokencircles-in iig. 2.

e l Suitable levers b are arranged to move the spindles endwise,hnt in use it is designed to have them fed ,automatically by a screw,

weight, or other ordinary mechanism.

C designates a revolving frame, provided with snitahle clamps c c c 0,'and revolving on anY axis, which is at au equal distance from 'they axis of each pair of lhc clamps may be4 arranged `to receive the main part of the shackle d, to which the ears are attached, or'to receive the shackle eye The frame C isY arranged to be stopped at each each quarterrevolution bythe pin e enteringthe frame C. While stopped in this manner, a shackle is e `placed with its clip-end? pointing iu a certaindirec-A tion, in the forward upper clamp, which clamp is not in front of either of the spindles; a quarter revolution brings it iu front of the rst or lower front pair of spindles a .th'e right-hand one of whichcarries a the body of the shackle-bolt, while the left-hand spindle carries a drill of a size proper to make a holersuitable to be threaded for ,the threaded end of the sameV bolt,

rlhe drills and spindles a, (t move forward simultaneously, and drill each of' the ears, while, at the same time, the operator places another shackle in the clamps e, taking care to place its clip-end in the opposite direction ti'om that of the one previously inserted, as shown in the drawing, by which means the. ears are properly drilled in pairs.` Another turn of the frame C, the shackle last placed in the clamps is drilled as before described, while simultaneously one of the rear lower spindles, carrying a tap, advances and threads the ear having the small hole, while, at the third pair ot spindles, a drill or reamer, simultaneosl y with all the former operations, trims out :he large hole, making them of a uniform size.

When eyes d are to be drilled, the tirst pair of spindles aa have drills of' an equal size in each, but are arranged so that one retreats sooner than the other, while the remaining drill finishes the hole. The next turn or stop of the frame C, the hole is sized by a drill or a=reamer, while, at .the third pair of spindles, a sweep or mill sweeps off the ends ofthe eyes d', making them of uniform length, andbringing vtheirendsy square with the hole. y

I claim as my invention- The revolving frame C,wheu 'provided with clamps c c c c, and arranged between `two series of revolving drills and taps a a a, substantially as and for the purpose described.

JAMES CLARK.

Witnesses i JAMES SHEPARD, C. A. SHEPARD. 

